Add diagnostics to Enphase Envoy (#79950)

* Streamline Enphase Envoy config flow tests

* Don't test data results using constants

* Add diagnostics to Enphase Envoy

* Use whole config entry

* Redact serial number

* One call

homeassistant/components/enphase_envoy/diagnostics.py

@@ -0,0 +1,38 @@
+"""Diagnostics support for Enphase Envoy."""
+from __future__ import annotations
+
+from typing import Any
+
+from homeassistant.components.diagnostics import async_redact_data
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.const import CONF_NAME, CONF_PASSWORD, CONF_UNIQUE_ID, CONF_USERNAME
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers.update_coordinator import DataUpdateCoordinator
+
+from .const import COORDINATOR, DOMAIN
+
+CONF_TITLE = "title"
+
+TO_REDACT = {
+    CONF_NAME,
+    CONF_PASSWORD,
+    # Config entry title and unique ID may contain sensitive data:
+    CONF_TITLE,
+    CONF_UNIQUE_ID,
+    CONF_USERNAME,
+}
+
+
+async def async_get_config_entry_diagnostics(
+    hass: HomeAssistant, entry: ConfigEntry
+) -> dict[str, Any]:
+    """Return diagnostics for a config entry."""
+    coordinator: DataUpdateCoordinator = hass.data[DOMAIN][entry.entry_id][COORDINATOR]
+
+    return async_redact_data(
+        {
+            "entry": entry.as_dict(),
+            "data": coordinator.data,
+        },
+        TO_REDACT,
+    )